One issue I have personal experience with is what's called "cooperative overlapping". In most corporate cultures, you're expected to nod along to what people say and reply only when they're finished talking. But in many people-group cultures, including my native one, talking over people is a neutral to positive thing showing your engagement with a conversation. (In fact, failing to interject can be negative in some contexts, signaling that you don't care at all what they have to say and you're just waiting for the babbling to stop.) I've learned to adapt to the degree that I'm seen as impatient rather than simply rude, but it requires substantial effort, and I'll probably never be able to do it as well as people who grew up with this style of conversation.